#pragma once

#include <iostream>
#include <cstring>
#include <string>
#include <sys/types.h>
#include <sys/socket.h>
#include <jsoncpp/json/json.h>

#define SEP " "
#define SEP_LEN strlen(SEP) // 不敢使用sizeof()
#define LINE_SEP "\r\n"
#define LINE_SEP_LEN strlen(LINE_SEP) // 不敢使用sizeof()

enum
{
    OK = 0,
    DIV_ZERO,
    MOD_ZERO,
    OP_ERROR
};

// "x op y" -> "content_len"\r\n"x op y"\r\n
// "exitcode result" -> "content_len"\r\n"exitcode result"\r\n
std::string enLength(const std::string &text)
{
    std::string send_string = std::to_string(text.size());
    send_string += LINE_SEP;
    send_string += text;
    send_string += LINE_SEP;

    return send_string;
}

// "content_len"\r\n"exitcode result"\r\n
bool deLength(const std::string &package, std::string *text)
{
    auto pos = package.find(LINE_SEP);
    if (pos == std::string::npos)
        return false;
    std::string text_len_string = package.substr(0, pos);
    int text_len = std::stoi(text_len_string);
    *text = package.substr(pos + LINE_SEP_LEN, text_len);
    return true;
}

// 没有人规定我们网络通信的时候，只能有一种协议！！
// 我们怎么让系统知道我们用的是哪一种协议呢？？
// "content_len"\r\n"协议编号"\r\n"x op y"\r\n

class Request
{
public:
    Request() : x(0), y(0), op(0)
    {
    }
    Request(int x_, int y_, char op_) : x(x_), y(y_), op(op_)
    {
    }
    // 1. 自己写
    // 2. 用现成的
    bool serialize(std::string *out)
    {
#ifdef MYSELF
        *out = "";
        // 结构化 -> "x op y";
        std::string x_string = std::to_string(x);
        std::string y_string = std::to_string(y);

        *out = x_string;
        *out += SEP;
        *out += op;
        *out += SEP;
        *out += y_string;
#else
        Json::Value root;
        root["first"] = x;
        root["second"] = y;
        root["oper"] = op;

        Json::FastWriter writer;
        // Json::StyledWriter writer;
        *out = writer.write(root);
#endif
        return true;
    }

    // "x op yyyy";
    bool deserialize(const std::string &in)
    {
#ifdef MYSELF
        // "x op y" -> 结构化
        auto left = in.find(SEP);
        auto right = in.rfind(SEP);
        if (left == std::string::npos || right == std::string::npos)
            return false;
        if (left == right)
            return false;
        if (right - (left + SEP_LEN) != 1)
            return false;

        std::string x_string = in.substr(0, left); // [0, 2) [start, end) , start, end - start
        std::string y_string = in.substr(right + SEP_LEN);

        if (x_string.empty())
            return false;
        if (y_string.empty())
            return false;
        x = std::stoi(x_string);
        y = std::stoi(y_string);
        op = in[left + SEP_LEN];
#else
        Json::Value root;
        Json::Reader reader;
        reader.parse(in, root);

        x = root["first"].asInt();
        y = root["second"].asInt();
        op = root["oper"].asInt();
#endif
        return true;
    }

public:
    // "x op y"
    int x;
    int y;
    char op;
};

class Response
{
public:
    Response() : exitcode(0), result(0)
    {
    }
    Response(int exitcode_, int result_) : exitcode(exitcode_), result(result_)
    {
    }
    bool serialize(std::string *out)
    {
#ifdef MYSELF
        *out = "";
        std::string ec_string = std::to_string(exitcode);
        std::string res_string = std::to_string(result);

        *out = ec_string;
        *out += SEP;
        *out += res_string;
#else
        Json::Value root;
        root["exitcode"] = exitcode;
        root["result"] = result;

        Json::FastWriter writer;
        *out = writer.write(root);
#endif
        return true;
    }
    bool deserialize(const std::string &in)
    {
#ifdef MYSELF
        // "exitcode result"
        auto mid = in.find(SEP);
        if (mid == std::string::npos)
            return false;
        std::string ec_string = in.substr(0, mid);
        std::string res_string = in.substr(mid + SEP_LEN);
        if (ec_string.empty() || res_string.empty())
            return false;

        exitcode = std::stoi(ec_string);
        result = std::stoi(res_string);
#else
        Json::Value root;
        Json::Reader reader;
        reader.parse(in, root);

        exitcode = root["exitcode"].asInt();
        result = root["result"].asInt();
#endif
        return true;
    }

public:
    int exitcode; // 0：计算成功，!0表示计算失败，具体是多少，定好标准
    int result;   // 计算结果
};

// "content_len"\r\n"x op y"\r\n     "content_len"\r\n"x op y"\r\n"content_len"\r\n"x op
bool ParseOnePackage(std::string &inbuffer, std::string *text)
{
    *text = "";
    // 分析处理
    auto pos = inbuffer.find(LINE_SEP);
    if (pos == std::string::npos)
        return false;

    std::string text_len_string = inbuffer.substr(0, pos);
    int text_len = std::stoi(text_len_string);
    int total_len = text_len_string.size() + 2 * LINE_SEP_LEN + text_len;

    if (inbuffer.size() < total_len)
        return false;

    // 至少有一个完整的报文
    *text = inbuffer.substr(0, total_len);
    inbuffer.erase(0, total_len);
    return true;
}